1. Field of the Invention
The present invention relates to an adapter device which can be inserted into an access opening in the rearward, handle portion of a screw gun which has been provided with means for accepting the adapter device. The screw gun is otherwise conventional having a spring biased clutch at its forward drive end that must be engaged before the screw gun will transmit rotational motion from its motor to its forward, output drive member. The present invention allows an adapter to engage the drive shaft of the motor from the rearward handle end of the screw gun to provide a rotatable cutting or drilling tool at the rearward handle end of the screw gun in a quick and easy manner thereby eliminating the need for a separate drill or cutting tool.
2. State of the Art
Conventional power tools as used in the drywall industry typically perform only one function. For example, a screw gun is used for inserting screw type fasteners or attachments through the sheets of drywall, and a separate, distinct router is used to cut openings in the drywall panels after they have been attached to their stud supports. Typical screw gun devices are shown in U.S. Pat. Nos. 2,857,997, 2,950,626, 4,159,050 and 4,804,048. Such tools allow the drive member to slip when a desired tightening torque has been attained in the screw type fasteners or attachments being driven through the drywall panels. However, such screw gun tools do not eliminate the need for the operator to carry a router tool in addition to the screw gun.
Generally, heretofore an installer of drywall typically employed a screw gun for securing the drywall to the framework along with a drywall cutout tool or router which is specifically designed for making cutouts in the drywall for electrical boxes, window openings, splices, etc. In U.S. Pat. No. 5,090,545 a modification of a conventional screw gun is disclosed in which a nose cone adapter is fit on the nose cone of the screw gun so that the screw gun can function both as a drive tool and as a drywall cutout device. Unfortunately, to fit on the nose cone of a conventional screw gun, the adapter must be of a size that is awkward in actual use. In addition complex mechanisms are required for activating and transmitting proper speed of rotation to the drive tool. The adapter tool of U.S. Pat. No. 5,090,545 is relatively expensive and cumbersome to use.
3. Objectives
A principal objective of the present invention is to provide a simplified, relatively small, inexpensive adapter for a screw gun which is attachable to the back side of the handle of the screw gun for readily converting the screw gun into a router or cutting member and back to a screw gun by merely attaching and removing the adapter in an access provided at the back side of the handle of the screw gun.
A further object of the present invention is to provide an adapter for the back side of a screw gun which is relatively simple to manufacture, install and operate.